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Assessing the validity of a real-world system with respect to given quality criteria is a common yet costly task in industrial applications due to the vast number of required real-world tests. Validating such systems by means of simulation…

Machine Learning · Computer Science 2024-09-06 David Reeb , Kanil Patel , Karim Barsim , Martin Schiegg , Sebastian Gerwinn

We derive a maximum a posteriori estimator for the linear observation model, where the signal and noise covariance matrices are both uncertain. The uncertainties are treated probabilistically by modeling the covariance matrices with prior…

Statistics Theory · Mathematics 2014-03-12 Dave Zachariah , Nafiseh Shariati , Mats Bengtsson , Magnus Jansson , Saikat Chatterjee

Standard cosmological analysis, which relies on two-point statistics, fails to extract the full information of the data. This limits our ability to constrain with precision cosmological parameters. Thus, recent years have seen a paradigm…

Computer simulations are invaluable tools for scientific discovery. However, accurate simulations are often slow to execute, which limits their applicability to extensive parameter exploration, large-scale data analysis, and uncertainty…

We investigate, in dark matter and galaxy mocks, the effects of approximating the galaxy power spectrum-bispectrum estimated covariance as a diagonal matrix, for an analysis that aligns with the specifications of recent and upcoming galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-12 Sergi Novell-Masot , Héctor Gil-Marín , Licia Verde

We propose a robust inferential procedure for assessing uncertainties of parameter estimation in high-dimensional linear models, where the dimension $p$ can grow exponentially fast with the sample size $n$. Our method combines the…

Machine Learning · Statistics 2015-03-19 Tianqi Zhao , Mladen Kolar , Han Liu

Analyses of the galaxy N-Point Correlation Functions (NPCFs) have a large number of degrees of freedom, meaning one cannot directly estimate an invertible covariance matrix purely from mock catalogs, as has been the standard approach for…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-02 Jessica Chellino , Alessandro Greco , Simon May , Zachary Slepian

We show how the massive data compression algorithm MOPED can be used to reduce, by orders of magnitude, the number of simulated datasets that are required to estimate the covariance matrix required for the analysis of gaussian-distributed…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-18 Alan Heavens , Elena Sellentin , Damien de Mijolla , Alvise Vianello

In the near future, the China Space Station Telescope (CSST) will obtain unprecedented imaging and spectroscopic data. The statistical errors in the cosmological parameter constraints will be reduced significantly. The corresponding…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-09 Zhao Chen , Yu Yu , Jiaxin Han , Y. P. Jing

We describe a method for forecasting errors in interferometric measurements of polarization of the cosmic microwave background (CMB) radiation, based on the use of the Fisher matrix calculated from the visibility covariance and relation…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Haonan Liu , Emory F. Bunn

Estimation of a sparse spectral precision matrix, the inverse of a spectral density matrix, is a canonical problem in frequency-domain analysis of high-dimensional time series (HDTS), with applications in neurosciences and environmental…

Methodology · Statistics 2025-11-11 Navonil Deb , Amy Kuceyeski , Sumanta Basu

We present the BACCO project, a simulation framework specially designed to provide highly-accurate predictions for the distribution of mass, galaxies, and gas as a function of cosmological parameters. In this paper, we describe our main…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-04 Raul E. Angulo , Matteo Zennaro , Sergio Contreras , Giovanni Aricò , Marcos Pellejero-Ibañez , Jens Stücker

We present a scheme to extend the halo mass resolution of N-body simulations of the hierarchical clustering of dark matter. The method uses the density field of the simulation to predict the number of sub-resolution dark matter haloes…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Raul E. Angulo , Carlton M. Baugh , Carlos S. Frenk , Cedric G. Lacey

Third-order weak lensing statistics are a promising tool for cosmological analyses since they extract cosmological information in the non-Gaussianity of the cosmic large-scale structure. However, such analyses require precise and accurate…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-26 Laila Linke , Sven Heydenreich , Pierre A. Burger , Peter Schneider

Over the next decade, improvements in cosmological parameter constraints will be driven by surveys of large-scale structure. Its inherent non-linearity suggests that significant information will be embedded in higher correlations beyond the…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Joyce Byun , Alexander Eggemeier , Donough Regan , David Seery , Robert E. Smith

Magnetic particle imaging reconstructs tracer distributions using a system matrix obtained through time-consuming, noise-prone calibration measurements. Methods for addressing imperfections in measured system matrices increasingly rely on…

Image and Video Processing · Electrical Eng. & Systems 2026-03-20 Artyom Tsanda , Sarah Reiss , Konrad Scheffler , Marija Boberg , Tobias Knopp

Cosmic shear is one of the most powerful probes of Dark Energy, targeted by several current and future galaxy surveys. Lensing shear, however, is only sampled at the positions of galaxies with measured shapes in the catalog, making its…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-31 Andrina Nicola , Carlos García-García , David Alonso , Jo Dunkley , Pedro G. Ferreira , Anže Slosar , David N. Spergel

In cosmology, emulators play a crucial role by providing fast and accurate predictions of complex physical models, enabling efficient exploration of high-dimensional parameter spaces that would be computationally prohibitive with direct…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-10 Deaglan J. Bartlett , Shivam Pandey

We present a method for estimating sparse high-dimensional inverse covariance and partial correlation matrices, which exploits the connection between the inverse covariance matrix and linear regression. The method is a two-stage estimation…

Machine Learning · Statistics 2025-05-13 Samuel Erickson , Tobias Rydén

This paper studies the multi-task high-dimensional linear regression models where the noise among different tasks is correlated, in the moderately high dimensional regime where sample size $n$ and dimension $p$ are of the same order. Our…

Statistics Theory · Mathematics 2022-06-16 Kai Tan , Gabriel Romon , Pierre C Bellec